Migrating and Upgrading to Joomla! 4.x • Re: Error Call to undefined method Joomla CMS Application

Hi
After upgrade to Joomla 4
When I want to edit a custom html site module, I got this error:

An error has occurred.
0 Call to undefined method Joomla\CMS\Application\AdministratorApplication::isAdmin()

You have an extension which is incompatible with J4 (and later).

I’d suggest (without too much knowledge, it has to be said!) that it might be one that installs a button or similar to your editor (TinyMCE).

Try disabling extensions/plugins that do this until you find the right one then update it (or uninstall it).

Statistics: Posted by JAVesey — Fri Feb 16, 2024 10:06 am

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